Due to increasing labor, transportation, and raw material costs, agricultural growers require efficient and economical fertilization and/or irrigation (e.g., “fertigation”) systems to continue providing abundant food to a growing population at a low cost. Although conventional fertilization and irrigation systems have improved significantly in the past few decades, recording and organizing information pertaining to the operation of agricultural sites (e.g., irrigation and fertilization schedules, targets for nutrient delivery, pH maintenance, equipment maintenance, etc.) is frequently performed manually by a technician (e.g., writing on sheets of paper). Manually recording information may lead to unforeseen inefficiencies and problems. For example, a technician may also overlook certain items of information or record information incorrectly.
In a conventional system, a user (e.g., a customer account manager) defines fertilizer targets for each crop (e.g., the amount of fertilizer and the schedule for applying the fertilizer). A field technician determines irrigation hours and timing, and goes to the site while the equipment is running. However, this requires communication (e.g., a phone call) between the technician and an irrigation manager. At the site, the field technician measures tank levels, calculates usage, calculates a target output for the next irrigation cycle, calculates pump settings based on the targets and irrigation hours, and adjusts stroke settings of the pumps to match the theoretical target settings. For adjusting pH, the adjustment of base (e.g., KOH) solution pump settings requires a recalibration of the acid solution pump as well, which can take 10-45 minutes. The field technician then fills out paperwork (e.g., 4 to 5 information sheets) by hand, including the pump settings, tank level measurements, fill information, target information and the various calculations. In some cases, the field technician takes a photo of each page of information and sends it to a data analyst. The data analyst receives, prints, and reviews the information sheet, and manually enters the data into a spreadsheet to generate a final summary report. In some cases, this cycle is repeated at least once per week (except for defining the fertilizer targets, which change less often).
FIG. 1 shows a method of fertilization and/or irrigation using a conventional, manual system. At 110, a user (e.g., a customer account manager) defines fertilizer targets for a given irrigation and/or fertilization (“fertigation”) field. Each of the targets may include an amount of fertilizer (e.g., in units of pounds per acre) and schedule (e.g., a frequency, such as daily or three times per week, for a period of time, such as one month, three months, or a growing period for a particular crop).
At 120, a field technician or data analyst determines irrigation hours (e.g., 8 AM to 3 PM every other day). The field technician or data analyst calls an irrigation manager to confirm the irrigation hours.
At 130, tank levels are measured, usage is calculated, and target outputs for the next irrigation cycle are calculated. Pump settings are calculated based on the target outputs and the irrigation hours. Stroke and speed settings of each pump (i.e., for each component being applied to the field) are adjusted to match the theoretical target settings. The theoretical target settings can also be set or adjusted manually or using empirical data and/or observations.
At 140, the pH is checked, and the acid and base pumps are started at or set to their minimum settings. The speed of the acid and base pumps is slowly increased over time until the target concentrations are reached, and then the rest of the pumps (e.g., the main irrigation pumps) are turned on as long as the pH is within the target range. When the target acid and base concentrations are reached and the pH is acceptable, the method proceeds to step 160. If the target acid and base concentrations are not reached and/or and the pH is not acceptable, the method proceeds to step 150. At 150, the acid pump is recalibrated. The pH of the treated irrigation water is monitored and the speed and stroke settings of the acid and base pumps are continuously adjusted (e.g., increased) to target concentrations while maintaining a specified and/or target pH (which may be within a target pH range).
At 160, a site sheet (which generally includes several sheets of paper) is manually filled out (e.g., using paper and pen). The site sheet includes blank spaces for the pump settings, the tank level measurements, any tank fill information, the target settings or other information regarding targets, and any calculations that were performed. At 170, the site sheet is transmitted to a data analyst. In general, the technician takes photos of the site sheet and sends the photos to the data analyst by email or text message (e.g., using a smart phone). Alternatively, the technician can transmit the site sheet to the data analyst by hand.
At 180, the data analyst prints and reviews the site sheet, manually enters data from the site sheet into a spreadsheet, and generates a final summary or report. At 190, the steps 110 to 180 are typically repeated at least once per week (except for defining fertilizer targets).
There are challenges and problems with recording and processing information in conventional manual fertigation systems. First, when an error in pH calibration is indicated, no reason may be given for the error. When neutralizing excess acid or base, the field technician slowly adjusts the stroke of the pump(s) to achieve a desired pH. However, this is time-consuming when done properly, and potentially dangerous if performed improperly (equipment and/or crop damage and personal injury may result). When monitoring the level of a chemical tank or measuring the level of liquid in the tank, the accuracy of this measurement depends on (1) using the same baseline spot or reference point to measure the tank level, and (2) the technician seeing the correct level in the tank (the approximate accuracy is ±1 inch, but may be larger for different technicians). The pump output is manually adjusted by a technician in the field approximately once per week by adjusting the stroke length of the pump after calculating a theoretical pump performance. However, over- and under-feeds (typically greater than 20%) based on weekly targets are common due to the variance of the actual pump performance from the theoretical performance. In turn, this causes non-linear feeds to meet final targets (e.g., for a monthly target of 30 lbs./acre, the target may be approached by feeding weekly amounts of 8, 5, 11, and 6 lbs./acre). Controlling the speed of a pump with a variable frequency drive is not possible due to overheating of the pump. Problematic and poorly performing pumps are recognized only by output monitoring after one or more site visits and manually entering and analyzing the data, thereby causing delays in identifying such pumps. Manual calculations and entry of data commonly result in errors in summary reports. Thus, there are needs to address the above challenges and problems in recording and analyzing information in conventional manual fertigation systems.
In addition, conventional fertigation systems can be monitored and/or adjusted only while a technician is at the site. Adjustments to the conventional fertigation system (i.e., changing a pump feed rate) results in a change in pH. This change in pH must be compensated by recalibrating the acid pump flow rate, which can only be done while water is running in the irrigation water supply line. If the technician visits the site when it is not running (i.e., when water is not being delivered to the crops), the technician cannot make adjustments to the site variables, and the technician's visit will be ineffective for at least part of the visit. Several hours per technician per week or more may be misused due to the site not running when the technician is present. Furthermore, an inability to adjust pump feed rates can cause improper feed rates and equipment malfunction.
This “Discussion of the Background” section is provided for background information only. The statements in this “Discussion of the Background” are not an admission that the subject matter disclosed in this “Discussion of the Background” section constitutes prior art to the present disclosure, and no part of this “Discussion of the Background” section may be used as an admission that any part of this application, including this “Discussion of the Background” section, constitutes prior art to the present disclosure.